Measuring learning curves allows for the inspection of the rate of learning and competency threshold for each individual, training lesson, or training method. In this work, we investigated learning curves in acupuncture needle manipulation training with continuous performance measurement using a vision-based needle training system. We tracked the needle insertion depth of 10 students to investigate their learning curves. The results show that the group-level learning curve was fitted with the Thurstone curve, indicating that students were able to improve their needle insertion skills after repeated practice. Additionally, the analysis of individual learning curves revealed valuable insights into the learning experiences of each participant, highlighting the importance of considering individual differences in learning styles and abilities when designing training programs.